Aerial photography helps you too.
By Alan Hassell ?
Copyright ? August 24, 1998
No part my be published without authors written consent.
One of the problems facing the Shallow water detectorists is the fact that even though much of a beach is visible to the human eye, just as much remains hidden from view. The reason for this is quite simple and obvious if you did but think about it, because it is covered with water.
If you are lucky enough to live in an area where you have large tidal flows, it is possible to see exactly what lies beneath the waves. Some individuals may not be so lucky, but can still see the environment they are interested in thanks to aerial photography.
Before any maps can be made, aerial photographs are first obtained before cartographers turn that photograph into what we call a map. Maps are used mainly as a form of guide to be used on land to get from point A to Point B.
In some instances they can be helpful in locating certain buildings and car parks on beaches but that is basically all they can do. Little attention is paid to the water and what lies under it.
The Aerial photograph on the other hand is a far greater tool for any Shallow Water Metal detecting enthusiast. Few rely upon them as the most reliable form of information available regarding a place of interest.
In fact the aerial photograph can tell the viewer much about a particular site. In many cases a great amount of detail can be seen and show to a reasonable degree of accuracy where the most productive parts of a beach are.
In my article, 'Dummies Guide to the Beach,' I attempted to explain in detail the effects of the wind and waves that constantly change the appearance of a beach. Without the aid of visual means this can be difficult for anyone to grasp the enormity of the subject.
Being able to produce a photograph on the Internet is of much greater benefit to the readers for you see and comprehend a visual description far better.
Those ridges close to the shore are the channels often mentioned in my articles.
Find these and the deepest parts are the most productive.
This particular photograph is of Frankston, beach in Victoria, Australia where I spent many hours recovering lost goodies. It is a very popular beach that attracts thousands during the hot summer days and nights.
Frankston was also made famous for many scenes for the film, 'On the beach which were shot in,and around the City . Forget about what you see inland, that's of no consequence or concern to you.
What you are looking at are those ripples in the water close to the beach itself. These are the famous channels I have mentioned time and time again in my articles. These are the areas that you stand a far greater chance of finding those goodies than anywhere else on the beach.
The first ripple is what is known as the nearshore channel because it just happens to be the nearest one to the beach.
The other one further away from the beach is the longshore channel. Both can be highly productive areas for wannabe wizards.
First we have waves racing their way upto the beach, which finally break and rush up the beach itself. This water on the beach is known as swash and must return from whence it came back into the water. When it does, the water returning upsets the flow of incoming water which races over the top of it in layers if you like.
Something interesting is going on in the water itself and an undertow develops. It's all to do with physics and expenditure of energy. Were it possible, the undertow would continue on its merry way except it reaches a point where the incoming water is greater than the returning water. It's something like a head on crash in a motor car if you like.
Water unlike motor cars must dissipate the energy built up; it does this by diverting itself in the same direction as the wind. Imagine if you can a situation where all of a sudden you reach the end of the road with no where to go but in one single direction because of the flow of traffic. Like it or not you have to follow that course, which is exactly what the water does.
When this happens the phenomenon is known as longshore or nearshore drift. It is these underwater tidal flows that gouge out the sand forming what you can see as channels. The forces at work in these channels can be quite severe and many tons of sand can be moved from one end of a beach to another in a very short space of time.
Not only will these underwater currents move sand but they will also move the very items you happen to be looking for depending on its strength. Bear in mind one interesting factor, gold has a specific gravity of 19.2.
Sand has an SG of 2.5 therefore the sand will always move a far greater distance than the gold. This is because once that underwater current loses its power gold will drop out, much the same as it does in natural river courses.
One would think that the pier, being a man made construction would be beneficial in stopping some of the gold. In some ways, it does and in many others it does not. Human being's being the animals we all are usually throw empty drink cans, bottles and other useless junk into the water rather than placing in a rubbish bin provided.
The closer you get to a pier the more junk you will encounter and have to dig. However some nice goodies have come from area's close to piers so they should not be dismissed completely. Depending on your area, one side of the pier will always be more popular with the bathers.
Find out what side that is, use this as a guide, however this does not mean that the other side of the pier will never be used.
Only time will prove which side is the most productive. In my case it was always the right had side. Back in the 60s a woman reported losing a very expensive diamond ring valued at $4000.00 at the time.
Since I started writing about Shallow Water Metal Detecting in the 80s numerous guys have looked for that same ring. Maybe the ring was never lost at all and was an excuse to rip-off the insurance company.
For try as I may, I never found it or have heard of anyone else finding it either. Rings like that are lost and quite often too.
The great thing about Shallow Water metal detecting is the fact that one day you might just be the person who locates a ring such as that. When and if you do, the price you paid for your metal detector is a mere pittance of the object that you recover.
As a bonus, you still have your metal detector to find more. For this reason you should always look at the cost of a detector as an investment.
One that will repay its initial outlay back to the owner many times over.
Since swimming became popular 100 years or more ago, people have been losing things in the water. They have been accumulating waiting for someone to come along with a metal detector to remove some of this expensive magic once in a while.
One man cannot search every inch of every beach so I pass this knowledge on in order that someone might realize that even a simple photograph can be a treasure in itself if it covers the area you are interested in. Happy hunting. ?
These days you dont need aerial photographs Google earth has made that far easier for you use it .
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